Charles A. Kupchan has written an important book that poses fundamental questions for international relations scholars and policy makers: First, how do enemies in world politics become friends? Specifically, through what pathways can pairs or groups of states succeed in setting aside their geopolitical competition and construct enduring relationships that preclude the possibility of armed conflict? Second, when and why do enemies become friends (and vice versa)? In other words, under what circumstances are such zones of peace more likely to form and under what circumstances are they likely to dissolve?

Introduction by Jeffrey W. Taliaferro, Tufts University

Charles A. Kupchan has written an important book that poses fundamental questions for international relations scholars and policy makers: First, how do enemies in world politics become friends? Specifically, through what pathways can pairs or groups of states succeed in setting aside their geopolitical competition and construct enduring relationships that preclude the possibility of armed conflict? Second, when and why do enemies become friends (and vice versa)? In other words, under what circumstances are such zones of peace more likely to form and under what circumstances are they likely to dissolve?

In How Enemies Become Friends, Kupchan directly challenges several bits of conventional wisdom: Neither shared liberal democracy nor high levels of economic interdependence are necessary conditions for the onset of stable peace. Pairs and sometimes groups of autocratic states are capable of exercising strategic restraint. Skillful diplomacy, not high levels of international trade and investment, is the key first step on the pathway to enduring peace. However, peace is more likely to endure when the states in question share three attributes: institutionalized restraint, compatible social orders, and cultural commonality. Zones of peace can take various forms ranging from a simple rapprochement between pairs of former adversaries, to the creation of security communities of several strategically proximate states, and, finally, to the union of several independent polities into a single sovereign state.

Drawing upon several different schools of international relations theories, principally the English School, but also some elements of constructivism, (neoliberal) institutionalism, realism, and Karl W. Deutsch’s functionalist work on security communities,[1] Kupchan develops a four-stage theory. The pathway to stable peace begins with one state’s unilateral accommodation to a former or potential adversary, which although driven by strategic necessity, might be interpreted by the other side as a sign of good will. In the second phase, the parties engage in reciprocal restraint by demonstrating a willingness to forgo short-term gains in favor of long-term cooperation. Societal integration follows in the third phase. As states and their societies become more integrated, confidence building gives way to mutual trust. In the final phase, elites and various interest groups within society generate new political narratives that stress common identities, the expectation of peaceful coexistence, and the illegitimacy of force as a means to resolve disputes.

Kupchan lays out his theory in the first two chapters. Chapter 3 examines rapprochement between the United States and Great Britain from 1895 to 1906. An examination of two additional cases of successful rapprochement—Norway and Sweden from 1905 to 1935, and Argentina and Brazil from 1979 to 1998—and two failed rapprochements—Britain and Japan from 1902 to 1923, and China and the Soviet Union from 1949 to 1960—follow in Chapter 4. Chapter 5 examines five cases of security communities. The three successful cases are the Concert of Europe from 1815 to 1848, the European Community (EC) from 1949 to 1963, and the Association of Southeast Asian States (ASEAN) from 1967 to the present. The two failures are the demise of the Concert of Europe from 1848 to 1853 and the Gulf Cooperation Council (GCC) from 1981 to the present. Chapter 6 examines unions: three successes—the Swiss Confederation from 1291 to 1848; the Iroquois Confederation from 1450 to 1777—and two failures—the United Arab Republic (UAR) of Egypt and Syria from 1958 to 1961 and the confederation between Senegal and Gambia from 1982 to 1989. This chapter concludes with additional cases studies of the creation of three unions—the United States in 1789, Italy in 1861, and Germany in 1871—and the dissolution of two unions—the outbreak of the U.S. Civil War in 1861 and the expulsion of Singapore from Malaysia in 1965. Chapter 7 summarizes the book’s findings and discusses implications for policy.

The three contributors to this roundtable agree that How Enemies Become Friends is an ambitious book. Greg Anderson writes it has been a while since he “read a piece of scholarship that is so sweeping in ambition (sorting out world peace) and systematic in terms of the development of a framework of analysis (the English School) and supporting evidence (the significant number of case studies).” Similarly, Stacie E. Goddard writes that Kupchan “refuses to be hemmed in by conventional paradigmatic debates in international relations” and “he is to be commended for reaching far beyond the typical selection of modern European cases to explore rapprochement between Argentina and Brazil, the ASEAN security community in Southeast Asia, and the pursuit of union among the Iroquois, the United Arab Emirates, and between Senegal and Gambia.” Even the most critical of the reviewers, Seva Gunitsky, acknowledges that How Enemies Become Friends “is unapologetically and pleasantly ambitious, clearly written, and wide-ranging in the scope of its historical cases,” but he also notes “its analytical model, clearly laid out in the opening chapters of the book, soon becomes untethered from the actual historical processes described in the subsequent case studies.”

“Bridging paradigms has become somewhat of a badge of honor in international relations theory,” Goddard observes, but “Kupchan’s commitment to breadth might come at the cost of depth and coherence in his theory.” Specifically, she questions the relationship among the variables in Kupchan’s theory, which at first glance, seems to posit that the process of peace building moves from the rational to the sociological. Yet, Goddard contends, in Kupchan’s case study of the Anglo-American rapprochement, shared narratives and common identity appear to do little of the causal work. Geopolitical calculations, namely the depth of British relative decline and threats to Britain’s interest in multiple theatres, led British leaders to cede hegemony in the Western Hemisphere to the United States. The rhetoric of a unique Anglo-Saxon bond may have been useful in selling retrenchment to the British public, but Goddard questions whether it was causal.

Of the three reviewers, Anderson explicitly situates Kupchan’s framework in the English School. He writes though, that “the English School generally, and Kupchan’s book in particular, repeatedly leave me wondering what phenomenon in international affairs cannot be explained by the English School?” Instead of generating a set of set of testable hypotheses, Anderson contends, the English School “is trying to be everything that all of the other paradigms are not by throwing everything but the kitchen sink in there as a variable.” While lauding efforts by English School theorists to “move the analysis of international relations beyond the central tenets of realism,” he also faults them (and by extension, Kupchan) for not looking more deeply at the domestic determinants of foreign policy, in particular the relationship between foreign policy elites and societal groups. Anderson questions the argument that casual mechanisms facilitate societal integration, or lack thereof. .

Anderson, Goddard, and Gunitsky question Kupchan’s criteria for case selection and the plausibility of alternative hypotheses in several of the case studies. Their respective critiques of the empirical chapters in How Enemies Become Friends also raise several questions about the role of relative power and strategic calculation, as opposed to institutionalized restraint and ideational factors, in the formation of zones of peace, whether rapprochements, security communities, or unions.

Goddard asks “With so many variables packed into his theory, there seems little room for alternative explanations of his case studies—if zones of peace are rational and ideational, if states commit to amity for both reasons of material interest and identity, then it becomes increasingly hard to imagine a case that would not fit Kupchan’s theory.” For example, Goddard asks, “Empirically, does it make sense to view German Unification as just a deeper version of the peace between Argentina and Brazil? Is the failed union between Senegal and Gambia comparable to the failed rapprochement between Britain and Japan in the early twentieth century?”

Gunitsky observes the Concert of Europe from 1815 to 1848, which Kupchan codes as a successful security community, in reality had neither of the prerequisites for stable peace posited by his theory—cultural commonality and compatible social orders. In fact, he contends, the restraint shown by Britain and Russia at the onset of the Concert stemmed from geopolitical necessities (i.e., Britain’s desire to restore the balance-of-power on the continent and Russia’s desire to avoid provoking its former allies), rather than a decision for unilateral accommodation.

Both Anderson and Gunitsky suggest that Kupchan’s account of the origins of the EC hinges on a selective reading of the historical record. Instead, both contend that the emergence of a Western European security community after 1949 was only made possible through the assistance and the acquiescence of the United States, chiefly through the Marshall Plan, NATO, and the presence of U.S. military bases. Anderson also questions how ideas about Franco-German reconciliation after World War II might have translated into foreign policy. He writes, “A number of the theoretical influences Kupchan borrows from for this volume entail the power of ideas to shape policy. Curiously, however, scant attention is paid to how these ideas percolate into the leadership that ultimately extends its accommodative hand.”

Gunitsky questions whether ASEAN is actually a security community at all, since economic integration remains limited and Thailand and Cambodia have an ongoing border dispute that could escalate to armed conflict. Goddard asks how Kupchan’s explanation of German unification in 1871 as a largely liberal and consensual enterprise might stack up with other accounts “prolific in the historiography, that emphasizes the coercive nature of Prussian-led efforts to create a unified sovereign state.”

Lastly, Anderson and Goddard question the extent to which Kupchan’s theory yields policy prescriptions. Goddard, for example, asks about the implications for U.S.-China relations, noting that Kupchan’s theory does not give policy makers in Washington much of a roadmap for how to overcome the social and cultural barriers to a possible Sino-American rapprochement. Kupchan, she argues, equivocates by saying while these ideational barriers matter they do “not mean that rapprochement between the United States and China is futile,” but instead suggest that “rapprochement is unlikely to occur as easily and extend as fully as that which occurred between the United States and Britain.” (413) Anderson notes that just as U.S. policy makers struggled to translate the insights gleaned from democratic peace and democratic transition theories into policy, they might similarly struggle to translate Kupchan’s theory into a practical plan of action for peace making.

In his response, Kupchan accepts that charge that his theory is synthetic and eclectic, writing that his “preference for the eclecticism and sociological bent of the English School is driven more by induction than deduction; the effort to explain stable peace led me in that intellectual direction.” He further acknowledges that How Enemies Become Friends puts many variables at play and that the theory is not parsimonious, but defends his choices on the grounds that the book is problem-driven, not theory-driven. In response to Anderson and Goddard, Kupchan argues that How Enemies Become Friends does indeed yield concrete policy prescriptions and sets out a diplomatic strategy for turning enemies into friends. Finally, Kupchan takes exception to Gunitsky’s critique of three of the twenty historical cases in How Enemies Become Friends and his assessment that the book’s “beautiful theory” is “killed by ugly facts.”

Participants:

Charles A. Kupchan is Professor of International Affairs at Georgetown University and Whitney Shepardson Senior Fellow at the Council on Foreign Relations. His most recent book is No One’s World: The West, the Rise of the Rest, and the Coming Global Turn.

Jeffrey W. Taliaferro is an Associate Professor of Political Science at Tufts University, where he has taught since 1997. His research and teaching focus on security studies, international history and politics, and U.S. foreign policy. He earned a bachelor’s degree in history and political science from Duke University and a Ph.D. in government from Harvard University. Professor Taliaferro is the author of Balancing Risks: Great Power Intervention in the Periphery (Cornell University Press, 2004), which won the American Political Science Association’s Robert L. Jervis and Paul W. Schroeder Award for the Best Book in International History and Politics. His articles have appeared in International Security, SecurityStudies, and Political Psychology and several edited volumes. He is co-editor, along with Steven E. Lobell and Norrin P. Ripsman, of Neoclassical Realism, the State, and Foreign Policy (Cambridge University Press, 2009) and of The Challenge of Grand Strategy: The Great Powers and the Broken Balance between the World Wars (Cambridge University Press, 2012). Professor Taliaferro is writing a book entitled The Primacy of American Power: Neoclassical Realism and U.S. Grand Strategies, 1940-present, which is under contract at Routledge, and co-writing (with Lobell and Ripsman), Neoclassical Realism: A Research Agenda, which is under contract at Oxford University Press.

Greg Anderson is an Assistant Professor in the Department of Political Science at the University of Alberta and earned his Ph.D. from the Paul H. Nitze School of Advanced International Studies of the Johns Hopkins University (Johns Hopkins/SAIS) in Washington, D.C. Anderson’s research interests broadly cover international political economy, Canada-U.S. relations, U.S. foreign policy, and U.S. foreign economic policy, including U.S. trade policy and trade policy institutions. From 2000-2002, he also worked in the Office of the United States Trade Representative as a policy analyst in the NAFTA office. Several publications include “Did Canada Kill Fast Track,” Diplomatic History, 36, no. 3 (June 2012): 583-624; “Securitization and Sovereignty in Post-9/11 North America,” Review of International Political Economy (Available online January 2012); and Greg Anderson and Christopher Sands, eds., Forgotten Partnership Redux: Canada-U.S. Relations in the 21st Century, (Cambria Press: Amherst, NY, 2011).

Stacie Goddard is Assistant Professor of Political Science at Wellesley College. Her research explores issues of identity, legitimacy, and conflict in international relations. Her articles have appeared in International Organization, International Security, International Theor , and the European Journal of International Relations. Her book, Indivisible Territory and the Politics of Legitimacy: Jerusalem and Northern Ireland, was published by Cambridge University Press in 2009.

Seva Gunitsky is an Assistant Professor at the Department of Political Science and the Munk School of Global Affairs at the University of Toronto. He received his Ph.D. from Columbia University in 2011. He is currently preparing his first book, Democracy and the Decline of Great Powers, which examines how periods of sudden rise and fall of leading states forged waves of democracy in the twentieth century. He has previously published articles in the Journal of International Affairs and World Policy Journal.

Review by Greg Anderson, University of Alberta

For comparatively junior scholars like myself, reviewing the work of others is always fraught with some peril since more seasoned scholars have produced nearly everything one has the opportunity to review. That book reviews are hidden away in the back pages of most journals provides some anonymity and immunity from rebuttal.

No such luxury exists in a forum like this, but the normal tension between praise and critique is tempered by the opportunity to offer some interactive food for thought. It’s in this latter spirit of putting forward a few thoughts for discussion that I hope my reaction to this book fits.

The Inter-Disciplinary Appeal

It has been a while since I have read a piece of scholarship that is both so sweeping in its ambition (sorting out world peace) and systematic in terms of the development of a framework of analysis (English School) and supporting evidence (the significant number of case studies). In fact, the case study approach taken by this book represents one of the volume’s greatest strengths. While some of the case studies are developed more thoroughly than others (U.S.-UK Rapprochement vs. Argentina-Brazil Rapprochement, for example), nearly all could stand alone as short histories of strategic, diplomatic, and cultural engagement. Moreover, while Kupchan covers several of the ‘usual suspects’ in dyads such as the United States and Britain or the Soviet Union and China, there are several others such as Norway and Sweden and the evolution of the Gulf Cooperation Council that are not a widely appreciated.

The basic thesis of Kupchan’s work is that a broad set of sequential conditions pave the way for the emergence and durability of peace, all flowing from strategic necessity: unilateral accommodation, reciprocal restraint, societal integration, and the generation of a communal identity. As more of these conditions are satisfied, the likelihood of peace moving from the relative shallowness of rapprochement, through security community, and finally the pooled sovereignty of union increases.

According to Kupchan, peace “breaks out” and remains stable in the presence of restraint that has been institutionalized and put into operation in a nation’s foreign affairs, coupled with a cultural commonality with a rival state, that can then be utilized to advance the third condition of stable peace, societal integration.

It is a compelling thesis that draws upon or flirts with theoretical paradigms and traditions throughout the social sciences and humanities. In fact, one of this volume’s strengths, in addition to the case study approach, is the thorough effort to develop the theoretical and analytical frame of reference through which the case studies are presented. Realism and its variants, yes, it’s in there. Liberalism and interdependence, they’re there. Is there any modernization theory or democratic peace theory? Check. How about the clash of civilizations? Yes, pretty close. What about some of the newish paradigms like constructivism? Yes, something here for everyone.

Like many scholars, my training and experience have me wearing different professional hats coupled with the frequent feeling of being something of a disciplinary fish out of water. Hence, for me, the breadth and diversity of Kupchan’s approach genuinely appeals.

Having been an historian until the completion of my Master’s degree, I find the the richness and breadth of Kupchan’s case studies to be appealing.Moreover, the elaborate theory development of the first seventy pages is all well and good for the historian, but it is the inter-temporal, comparative narratives about why peace breaks out, succeeds, or fails that really drive this thesis. As my research and teaching have drawn me further into economic literature, I am struck by the second-tier status Kupchan assigns to economic interdependence as a driver of peace (more on this below). However, it is as a political scientist that Kupchan’s volume evokes my strongest reaction.

The English School

Having been trained in the United States, I am, for good or for ill, among those who think in largely positivist terms about social science research. Moreover, a strong focus on American foreign policy reaffirmed the primacy of realism in foreign policy thinking. Liberal theories, interdependence theorists, modernization theorists, Marxists and constructivists all had interesting things to say, but all roads seemed to revert to realism.

Many of my Canadian colleagues represent a blended tradition of positivism and reflectivism, a hybrid of positivist American scholarship and the post-modern approaches of the Copenhagen or Frankfurt Schools.[2] Robert Cox and Antonio Gramsci are not unknown in America, but are far from household names in foreign policy. Canada is also home to many adherents of the English School that forms the backbone of Kupchan’s analytical frame. The inter-disciplinarian in me appreciates the English School’s mixture of hard-headed realism mixed with a range of influences from other paradigms, notably constructivism, that are, some would argue, so obviously a part of understanding international relations and the establishment of peace.

The positivist in me also sees many of the problems with the English School, many of which have been detailed elsewhere and don’t need repeating here in great detail.[3] However, the English School generally, and Kupchan’s book in particular, repeatedly leave me wondering what phenomenon in international affairs cannot be explained by the English School? Rather than a set of testable propositions, the English School seemingly borrows from too many other traditions to become a systematized framework for looking at international relations, much less as a prescriptive guide to foreign policy-making. In essence, the English School is trying to be everything that all other paradigms are not by throwing everything but the kitchen sink in there as a variable (all things to all people). But in doing so, the English School becomes unwieldy as theory, which partly explains why so little theory building has been done within the English School tradition.

That said, the narrowness of neorealism’s dominance of foreign policy is equally troubling given the ever-changing nature of international affairs, and the efforts by English School adherents to move the analysis of international relations beyond the central tenets of realism is laudable. This is particularly so since it seems the narrower and more methodologically rigorous we become, the less we are actually able to explain. Yet, it is hard to see how Kupchan’s conclusions about the early stages of successful peace building can be replicated for foreign policy. At some point early in each of the case studies, there was a unilateral gesture or concession made by one state seeking accommodation, often for geostrategic reasons. What is unclear from Kupchan’s analysis is whether the assessment of the rationale for these gestures on the part of the “state” was in fact the rationale as the state’s leadership envisioned it. Hence, while English School analyses have a statist orientation pleasing to realists, their efforts to broaden their analyses don’t look very deeply into the domestic determinants of foreign policy decision-making—often a critique levied at realism as well. The English School’s focus on the typology of the ‘international system,’ international society,’ and ‘world society’ broadens, but does so without looking deeply at the state itself. What, for example, are the causal mechanisms facilitating societal integration, or lack thereof? How would we know them if we saw them, and how could they be fostered? At what point does a shared narrative resonate and take hold below the level of elites who may have driven rapprochement, security community, or union?

We have seen these issues play themselves out repeatedly in contemporary Europe with the challenges of ratifying the European Union Constitution (now Lisbon Treaty), and of course the divisions sown by Europe’s debt crisis. In North America, considerable integration has taken place amongst Canada, the United States, and Mexico since the North American Free Trade Agreement (NAFTA) came into force in 1994, but it has proven difficult to foster a shared narrative of what it means to be a North American. This has been especially difficult for Canadians and Mexicans, and what once seemed to be a promising trilateral community of states has in the last decade actually reverted to two, highly asymmetrical, bilateral relationships with Washington.

Historians, for example, might be concerned with Kupchan’s analysis being a bit ‘Whig-ish” in that little effort is made to delve inside decision-making processes as they were perceived by those engaged in them. Kupchan makes a compelling case for British-Japanese rapprochement, for example. But someone had to initiate the matter from Britain’s side of the ledger. Yet, we know little about internal determinants of UK policy toward Japan in this period from this particular account other than the strategic necessity of shoring up British strategic weakness in the western Pacific. The argument is certainly plausible, but there must have been considerable debate in the UK over the merits of an alliance with such a distant partner.

Given the English School’s constructivist influences, the cognition behind many of the domestic determinants of foreign-policy making in Kupchan’s initial phase of unilateral accommodation by one party or another would seem a fruitful place for examining some of the earliest conditions leading to accommodation.

As I thought about these issues, I was reminded of the debates in the democracy literature oriented around sequencing.[4] Kupchan nicely demonstrates the outbreak of peace does not require the presence of liberal democracies—this may actually be one of the book’s strongest sets of conclusions. However, the circumstances of the “institutionalized restraint” so key to Kupchan’s analysis are in need of specification. Debate rages in the democracy literature over how to build institutions that facilitate the consolidation of embryonic democracy movements. How do states make the transition from opening, through consolidation, and onto stable genuine democracy? How can we avoid the stage of democratic development that avoids middle ground clichés captured by terms like semi-democracy, façade democracy, pseudo-democracy, illiberal democracy, or partial democracy?

With respect to peace-building, Kupchan nicely describes what some of the conditions favorable to peace are, but gives no indication as to how one might avoid reasonably giving many of his case studies labels such as semi-peace, façade peace, pseudo-peace, or illiberal peace. How Enemies Become Friends places considerable emphasis on the role of “institutionalized restraint” in the initial phases of peace building. But we need more research into conditions that pre-date that institutionalization, particularly in non-democratic states, for that may be where the building blocks of stable peace actually reside. If “institutionalized restraint” is a variable in both U.S.-UK and Sino-Soviet rapprochement, we ought to be looking deeper into the nature and origins of that “restraint” since it evidently comes in all shapes and sizes.

Just as policy makers have struggled to translate principles into policy in democracy promotion, they might also struggle to translate Kupchan’s argument into a practical course of action for peace making. When might we see conditions ripen for peace? How is a statesman to know when the time is right for a bit of unilateral accommodation? When will such gestures be reciprocated and for how long? How do we move from the comparatively shallow phase of rapprochement to the deeper forms of regime Kupchan describes such as security community or union? Because these questions don’t have the kind of ready policy prescriptions that flow from realism, it’s easy to appreciate realism’s appeal for policy-makers who would rather be safe than sorry.

Many readers of this forum will be familiar with the decades-long debates over the impact on the conduct of the Cold War of Kennan’s ‘Long Telegram’ or NSC-68. The interpretation of Soviet actions, and American policy responses, were filtered through this lens in the earliest days of the Cold War, heavily determining the evolution of the standoff thereafter. How might Kupchan’s approach handle a series of counter-factual “what ifs” from the earliest days of the Cold War? Why, for example, were acts of accommodation with respect to integrating the Soviets into the postwar financial architecture (Bretton Woods, including the International Trade Organization) rebuffed?[5] As Kupchan argues, the presence of democracy on all sides is not a necessary condition for peace. There was a reasonable chance for deeper cultural and societal integration, both sides having just worked to defeat the Axis Powers (generation of a communal identity).

As importantly, how might Kupchan handle the end of the Cold War 1989-1991? Were Mikhail Gorbachev’s 1986 proposals to dramatically reduce intermediate nuclear missile numbers in Europe a form of unilateral accommodation? Was Ronald Reagan’s proposal at Reykjavik, Iceland later that year to eliminate them altogether a form of reciprocation? How might we explain the subsequent debates in the late 1990s over “who lost Russia” as the Rubble collapsed and Russia descended into kleptocracy and authoritarianism? Have efforts to “hit the reset button” in U.S.-Russian relations all been for naught? Are we in the midst of the breakdown of rapprochement? Is it possible we might conclude that the most important conflict of the late 20th Century ended with relatively little bloodshed, but that former “enemies” never really became “friends?”

The point is that sorting through a lot of these questions and testing more of the English School’s foundational premises may be the only path toward transforming the compelling narratives offered by Kupchan into policy recommendations that can compete with those put forward by realists.

Other Food for Thought

I felt to some degree that some of Kupchan’s narrative hinges on a somewhat selective reading of the historical record. This was particularly striking in his description of the earliest days of the European Community wherein the conventional tale of economic integration leading political integration is turned upside down. One could probably quibble for some time over whether the intellectual origins of EU integration were essentially political or economic. But here I would point once again to the importance of getting inside the heads of those who were driving the process. Of particular note here is Jean Monnet, the architect of European integration, who is mentioned only once in the whole volume. I think the historical record suggests that he was a major force for European integration and that economic integration as a pathway to peaceful political integration was foremost in his mind. Importantly, Monnet was not an elected leader, but an intellectual and diplomat with no power to be making overtures to Germany on behalf of France. A number of the theoretical influences Kupchan borrows from for this volume entail the power of ideas to shape policy. Curiously, however, scant attention is paid to how these ideas percolate into the leadership that ultimately extends its accommodative hand. Fewer case studies might have undermined the demonstrative power of some of Kupchan’s arguments, but would also have allowed a deeper examination of these issues within those cases that remained.

However, an even more important structuring factor in the European story is the Cold War and the omnipresence of the United States itself. I have no quibble with Kupchan’s view that European integration required the acquiescence and vision of enlightened leadership in Europe itself. However, it’s hard to envision European integration evolving as it did without the sustained and structuring presence of the United States. American leadership with The Marshall Plan (1948), NATO (1949), the Berlin Airlift (1948), the United Nations (1945), and even the creation of the General Agreement on Tariffs and Trade (1947) powerfully structured the milieu in which France contemplated its initial accommodation of Germany with the European Coal and Steel Community in the early 1950s. It’s clear from Kupchan’s work that the atmosphere in which strategic necessity arises and prompts accommodation is key. In my view at least, Kupchan skates thinly over the role this may have played in the French calculus about strategic necessity.

With the exception of case studies dealing with the Concert of Europe and ASEAN, How Enemies Become Friends is largely a tale of bilateral peace making. The Concert and ASEAN are important exceptions here, both reaffirming one of Kupchan’s key, and important, arguments that liberal democracy is hardly a necessary condition for the establishment or maintenance of peace. However, each of these multilateral examples is largely in keeping with the English School’s largely statist foundations. I wondered throughout the volume how the English School, and Kupchan in particular, would treat the evolution of the Bretton Woods system, and the global trading regime in particular? Realists see this system as just another venue structured and utilized by major powers in the pursuit of self-interest.[6] Yet, how might Kupchan handicap the influence of these kinds of institutions in structuring the world system, and then constructing both international and world society?

How can we account for the peace-building utility of multilateral institutions themselves? The GATT in particular has grown from a mere 23 members to over 150 today, including many illiberal states (China since 1999, Russia 2012). The Bretton Woods system does not operate today as designed, but its legacy, including the IMF, World Bank, and the WTO, remains acutely important to the peaceable management of global affairs. By asking this question, I am perhaps placing myself among those scholars attracted to a more traditional liberal frame of reference regarding the postwar intellectual rationale for institutions on the part of people like Harry Dexter White, Jean Monnet, or Cordell Hull. I am not entirely sure all the elements of Kupchan’s thesis can be grafted here, but How Enemies Become Friends most certainly has me thinking about it and I would like to hear how Kupchan might treat this.

And finally, perhaps the greatest compliment one can offer any piece of scholarship like this is that it provoked a lot of thinking. Here, Kupchan has done that and more with How Enemies Become Friends. Any failings with this volume, or the English School framework Kupchan pursues, are far outweighed by the hope that this volume will invigorate more work on the English School to pull it out of the shadows of International Relations scholarship. Its nuanced realism has always held the promise of wiggling its way more firmly into the halls of power. It is my hope that How Enemies Become Friends will illicit more of the work needed to get it there.

Review by Stacie E. Goddard, Wellesley College

Life under anarchy is often portrayed as nasty, brutish, and short. Yet in the midst of heated anarchic competition, stable zones of peace can emerge: states form relationships in which violence is not only absent in the moment, but where violent conflict has become practically unthinkable. At the turn of the twentieth century, Britain and the United States achieved a “rapprochement” as they moved “away from armed rivalry to a relationship characterized by mutual expectations of peaceful coexistence” (30). In the Concert of Europe, in the European Union, and in ASEAN, stable zones of peace appear as security communities, characterized not only by peaceful coexistence, but by stable norms, rules, and a sense of collective identity that transcends the boundaries of individual nation states. The deepest form of stable peace are unions—think the creation of the United States or German Unification—where once sovereign or even rival units “not only see each other as benign, but they merge into a new polity,” thus fully escaping the perils of anarchy (31).

For many international relations theorists, the existence of stable zones of peace is a puzzle: how is it that states, once so suspicious of each other’s intentions, can come to view each other as friends? On the face of it, Charles Kupchan’s book provides a simple answer: it is diplomacy that drives stable zones of peace. Specifically, Kupchan outlines a four-stage process in which states transform their enmity into amity. It begins with a state’s unilateral signal of accommodation, perhaps making itself unnecessarily vulnerable to another’s exploitation, for instance. This leads to the diplomacy of reciprocal constraint, where both states indicate that they are willing to forgo short-term strategic gains to ensure future cooperation. States’ societies then attempt to integrate, with ties forming between states at both the elite and the mass level. In the final phase, states generate new narratives about their friendship. In the case of rapprochement, state leaders highlight their separate but compatible identities: Britain and the United States created a narrative which emphasized their shared historical and ethnic bonds, for example. In the case of union, states subsume their individual identities under a unified narrative, and “embrace a common identity” (50).

This all might seem intuitive, but to reduce Kupchan’s theory to “it’s the diplomacy, stupid,” does not do the argument justice. Kupchan is careful to note that diplomatic engagement is only possible under three conditions. The first, institutional restraint, is not technically a necessary condition, but it certainly helps ease the transition to peace: institutions that check a leader’s whimsical pursuit of power, that make intentions transparent and foreign policy credible allow states to make that first, significant unilateral accommodation as well as build patterns of reciprocal constraint. More necessary to a lasting peace, Kupchan argues, are shared social orders and cultural commonality. Without complementary domestic, economic and social systems, the social integration that solidifies rapprochement, community and union is likely to fail. Likewise, when substantial ethnic, religious, and racial cleavages exist, this can reinforce feelings of otherness, and undercut the narratives of collective identity necessary to building a lasting peace.

How Enemies Become Friends is breathtaking in its ambition. Theoretically, Kupchan refuses to be hemmed in by conventional paradigmatic debates in international relations, and instead provides an eclectic account that draws from “a combination of rationalist and sociological processes, and realist, liberal, and constructivist explanations” to “describe the formation of zones of stable peace as accurately as possible” (21). Kupchan’s empirical work is sweeping as well, and he is to be commended for reaching far beyond the typical selection of modern European cases to explore rapprochement between Argentina and Brazil, the ASEAN security community in Southeast Asia, and the pursuit of union among the Iroquois, the United Arab Emirates, and between Senegal and Gambia.

Given its scope, there is no doubt that Kupchan’s work will become a must-read for those interested in the construction of international society. But ambition can be a double-edged sword, and many of the problems that undercut Kupchan’s thesis are born of the book’s broad approach to theory, history, and policy. To begin with, there is the question of how Kupchan frames what it is he is trying to explain. Kupchan treats “rapprochement,” “security communities,” and “union,” as belonging “to the same family,” best seen as “stages along a continuum; as the parties move from rapprochement to security community to union, stable peace deepens and matures” (30). But are all of these phenomena simply differences in degree on the same dependent variable? Empirically, does it make sense to view German Unification as just a deeper version of the peace between Argentina and Brazil? Is the failed union between Senegal and Gambia comparable to the failed rapprochement between Britain and Japan in the early twentieth century? Defining the scope of inquiry broadly gives Kupchan impressive reach, but it might also be cover up serious differences in the phenomena Kupchan is trying to explain.

This is more than a matter of properly defining the universe of cases. Kupchan’s broad definition of “zones of peace” stretches not only the phenomenon he is trying to explain, but also the explanatory scope of his theory. Not surprisingly, when a dependent variable contains such a wide range of cases, the explanation risks becoming overly expansive as well. For example, in Kupchan’s story, states first seek to build peace out of strategic necessity. But what is strategic necessity? It seems to be anything that makes a state want to create a zone of peace: pressures for retrenchment in the case of Britain, domestic uncertainty in the case of ASEAN and the Gulf Cooperation Council. Indeed so broad is the condition of “strategic necessity” that it comes close to suggesting that states form friendships when it is in their interest to form friendships—true, perhaps, but not as analytically stimulating as a theory that specifies what types of strategic constraints are likely to lead to peace. A similar question arises with Kupchan’s definition of constraint. Kupchan argues that while rapprochement depends upon internal constraint—that is to say, domestic institutions that constrain leaders and provide transparency—security communities rely upon co-binding: the parties “bind themselves to one another through informal pacts or codified agreements that institute restraint and specify the terms of a rules-based order” (42). But are “self-binding” and “co-binding” really two sides of the same coin, or are they fundamentally different causal processes, ones which lead to drastically different forms of peace in the international system?

This discussion of theoretical scope brings up a second point. Bridging paradigms has become somewhat of a badge of honor in international relations theory, and certainly one cannot help but be impressed with the sweeping theoretical architecture Kupchan is bringing to the table. But here again Kupchan’s commitment to breadth might come at the cost of depth and coherence in his theory. Most notably, what is the relationship among the causal factors in Kupchan’s account? Kupchan provides what appears at first to be a fairly straightforward answer to this question: processes of peace-building move from the rational to the sociological. All zones of peace, be they rapprochements, security communities, or unions, begin with rationalist motivations: states accommodate others to preserve their strategic interests. But a truly stable zone of peace is as much discursive and ideational as it is strategic, and depends upon social integration and identity change to cement amity among states.

Yet this relationship among variables seems less simple once one delves into the case studies. In the Anglo-American rapprochement, for example, shared narratives and identity seemed to do little causal work. Ultimately, Kupchan’s story about the creation of the “special relationship” is grounded, first and foremost, in geopolitics: Britain, facing overstretch, realized it could not hold the Western Hemisphere, and wisely turned the area over to its (then junior) partner, the United States. Perhaps the rhetoric of a unique “Anglo-Saxon” bond was useful in selling retrenchment to the British public, but was it causal? Here, discourse and narrative seem a decorative sprinkling on top of the firm foundation of strategy necessity. In contrast, the entirety of the British-Japan rapprochement attempt foundered on narratives of race—when strategic necessity should have called for peaceful coexistence, cultural differences proved fatal.

The benefit of narrowing explanations, of establishing exactly when and why certain causal factors are important, is not simply theoretical. The breadth of Kupchan’s theory impacts how he presents his case studies as well. With so many variables packed into his theory, there seems little room for alternative explanations of his case studies—if zones of peace are rational and ideational, if states commit to amity for both reasons of material interest and identity, then it becomes increasingly hard to imagine a case that would not fit Kupchan’s theory. This is particularly problematic, because Kupchan’s explanations for his cases would be strengthened if compared to plausible competing explanations. In the Anglo-Japan case of failed rapprochement, for example, how much more does Kupchan’s theory about racial and cultural fault-lines tell us than, say, an explanation that stresses Britain’s strategic need to accommodate American antipathy towards Japan?[7] Similarly, Kupchan uses his theory to draw a picture of German Unification as a largely liberal and consensual enterprise, and one wonders how this stacks up to accounts of German Unification, prolific in the historiography, that emphasizes the coercive nature of Prussian-led efforts to create a unified sovereign state.[8]

Finally, more fine-grained causal explanations might have helped specify Kupchan’s policy recommendations as well. Kupchan’s focus on diplomacy does a nice job tearing down much of the conventional wisdom guiding IR theorists and policy-makers alike. Most notably, stable zones of peace, Kupchan insists, stem neither from the roots of democracy nor from economic integration. While it is true democracies may be better able to practice strategic constraint, for example, this strategy is not the exclusive province of democratic regimes: autocracies, too, are capable of self-binding. And while economic integration is key, Kupchan argues that such ties flow from, not cause, political decisions to build a stable peace.[9]

Kupchan’s critiques are bold, but his own policy prescriptions are less concrete than one might desire. What, for example, are the implications of Kupchan’s theory for U.S.-China relations? While he insists that he is not presenting a Huntingtonian “clash of civilizations” model of U.S.-China relations, his theory does not leave policy-makers with much of a roadmap to understand how culture will affect relations between these two great powers. Kupchan himself seems to equivocate on this question. Serious differences in social orders and culture exist, and while these do “not mean that rapprochement between the United States and China is futile,” they do suggest that “rapprochement is unlikely to occur as easily and extend as fully as that which occurred between the United States and Britain.” (413). This seems rather vague, and without a clearer understanding of how narratives are formed, and without a more developed discussion of the process through which actors may construct and reconstruct mutual identities, it is hard to pinpoint how culture might ultimately affect U.S.-China rapprochement.

In the end, How Enemies become Friends offers scholars and practitioners alike a bold vision of international society. In a time of potential power transitions, there is perhaps no more significant inquiry, and Kupchan is to be applauded for this work. Hopefully both the ideas contained in the book—as well as the critiques that it generates—will fuel productive arguments about the sources and possibilities of a stable peace.

Review by Seva Gunitsky, University of Toronto

Aldous Huxley once lamented that many beautiful theories have been killed by ugly facts, and Charles Kupchan’s book offers another illustration of this unfortunate fact. How Enemies Become Friends seeks to provide a general framework for the causes of stable peace among nations, but its analytical model, clearly laid out in the opening chapters of the book, soon becomes untethered from the actual historical processes described in the subsequent case studies.

To explain the outbreak and maintenance of peace among former rivals, Kupchan employs a four-stage process. First, a state offers reconciliation to a rival with an act of unilateral concession, a peace offering designed to signal benign intentions. Peace begins, on other words, with a show of weakness through “costly and unambiguous acts of accommodation” (40). But while Kupchan takes care in his case studies to contrast successes (durable unions and stable security communities) with failures (broken unions and collapsed security communities), there is a much larger universe of failures that are never discussed in the book, which are cases where peace was never attempted. How many demonstrations of weakness – Kupchan’s ostensible catalysts of stable peace – have led to war rather than mutual accommodation? How many unilateral concessions provoked a call to battle rather a truce?

A tension also arises in this stage between a nation’s strength and weakness. The accommodating state begins in a position of “peril”; it faces “an array of threats against which it has insufficient resources” (37); this weakness, in fact, is why it makes sense to accommodate in the first place. Yet in order for the act to be effective, Kupchan notes, the conceding state must also be a powerful rival; otherwise, accommodation seems like “an act of submission or desperation rather than a signal of benign intent” (41). The state that begins the process of peace-building, in other words, must be in a condition both perilous and powerful, simultaneously weak and threatening. This is not totally implausible – there may be short windows of opportunity for peace when state leaders perceive themselves to be in a weakened position, and act on it before other states can recognize and take advantage of this fact. As it turns out, this Goldilocks possibility is irrelevant: as the case studies show, when successful security communities are created, they never begin with an act of unilateral concession.

Once the opening concession is accepted and reciprocated, states begin the second stage of Kupchan’s process – reciprocal restraint, in which they “readily practice accommodation,” (41) and dampen their rivalry. In the third stage – societal integration – interactions increase not only at the elite level but also among firms, bureaucracies, and private citizens. Trade and investment expand; communications and cultural exchanges flourish. Finally, in the fourth stage, the actors undergo a profound normative transformation and forge a communal identity.

This arc of progress is made possible through three elements. The first is institutionalized restraint, which roughly approximates liberal democracy. It is a facilitating but not a necessary ingredient – autocracies can oppress their own citizens but still “practice strategic restraint in the conduct of statecraft” (53). The other two factors, however, are necessary pre-requisites for stable peace. These are 1) compatible social orders (based on the distribution of political and economic power among social classes and ethnic groups), and 2) cultural commonality (based on religion, race, or ethnicity).

This is Kupchan’s roadmap to peace; it is parsimonious and clear. It possesses both the boldness of simplifying assumptions and the humility to recognize them as such: thus, it is not a general theory of peace, and “no single story emerges” (11) from the case studies, as Kupchan is quick to point out. His claim, instead, is that there are recurrent patterns in the outbreak and maintenance of peace. But in the case of security communities – the most important element of international peace – these patterns are hardly to be found at all.

Three successful cases of stable security communities are examined in the book: the Concert of Europe (1815-1848), the European Community (1949-1963) and ASEAN (from 1967). How well do these follow the above framework?

The Concert of Europe was forged in the aftermath of the Napoleonic wars and held together with moderate success until the Spring of Nations finally tore it apart. It was not a true security community, as Kupchan admits, since war among its members did not become unthinkable and “strategic rivalry continued to animate their relations”; nevertheless, this rivalry was muted enough, he argues, to permit the classification (189).

The strangest element of the case study is that neither of Kupchan’s pre-requisites, posited to be necessary for stable peace – cultural commonalities and compatible social orders – were actually present in the Concert. As Kupchan notes, “there was not a high degree of cultural commonality among Concert members.” Moreover, its five members had “diverse social orders” (197). Finally, there was no institutionalized restraint among its members, Kupchan’s third (facilitating but not necessary) factor. Instead, there was “considerable diversity as to regime type” (197), with limited democracy in Britain and France and unchecked autocracy in Russia, Prussia, and Austria. And while Kupchan stresses that the Concert began with acts of restraint by both Britain and Russia, this restraint stemmed not from the desire for unilateral accommodation but from geopolitical necessities – neither could afford to provoke the rest of Europe by over-reaching, while Britain also sought to re-establish a balance of power on the continent. Where Kupchan expects concession we see restraint, yet the two are hardly synonymous.

The disconnect continues in the case of the European Community. This case study rests in the shadow of a barely-mentioned colossus – the power of the United States after 1945. To the extent that France practiced restraint against Germany after World War II, it did so under duress from the U.S. In fact, the security community itself was only made possible by the assistance and acquiescence of the American superpower, which forged the EC through economic aid and institution-building . The U.S., however, does not fit into the four-stage framework, and is thus neatly excised from the discussion after a token discussion of the Marshall Plan (which does not appear in the index).

Like the Concert of Europe, ASEAN is a questionable case of a security community. (Kupchan admits as much on p.34.) War among members is not only “thinkable” but real, with ongoing border clashes between Thailand and Cambodia. Economic integration, a symptom of the third stage of peace, remains “quite limited”, as Kupchan notes, as does societal integration (229). And the common factors behind ASEAN’s origins likely had more to do with anti-Communism and fear of Indonesia than cultural commonalities or compatible social orders.

In short, the recurring patterns that Kupchan aims to illuminate seem to hardly recur at all. The necessary pre-requisites of cultural commonalities and compatible social orders turn out to be unnecessary in 1815 and hardly visible in 1967 (they are more visible in 1945, but even then, a common European identity was more of a byproduct of the EC than its cause). Unilateral concessions are nowhere to be found; reciprocal restraint and societal integration are either lacking or forged by outside actors. Both the Concert and the EC seem to have been born out of the unique circumstances created by hegemonic wars, not peaceful bilateral accommodations. How well can a framework describe the general patterns if its basic elements are consistently lacking in the actual cases? Alas, the ugly facts have killed another beautiful theory.

For all these faults, the book is unapologetically and pleasantly ambitious, clearly written, and wide-ranging in the scope of its historical cases. It integrates insights from a number of international relations approaches and eschews the confines of paradigmatic divisions. Rationalism and constructivism work together; realism and liberalism are intertwined. This kind of puzzle-based rather than paradigm-based approach is a welcome continuation of recent trends in international relations theory. As another plus, unconventional wisdom undergirds some of Kupchan’s basic conclusions – the book effectively questions democratic peace theory as a source of interstate stability and reverses the notion, beloved by globalization enthusiasts, that political rapprochement flows from economic ties. Reading the final chapter reminded me of the adage that it is better to be wrong but interesting rather than right and trivially true. The book certainly does not aspire for the safety of the trivially true – so much so that it doesn’t seem true at all.

Author’s Response by Charles Kupchan, Georgetown University and Council on Foreign Relations

I am honored that H-Diplo has organized an exchange of views on How Enemies Become Friends, and am grateful to the participants for the time and effort they devoted to the book. The critiques offered by the reviewers are rich and thoughtful. I write this response not as a rebuttal or rejoinder, but as an effort to pick up on and push forward the important themes raised by this set of constructive reviews.

As the reviewers all note, How Enemies Become Friends is an ambitious book in both theoretical and empirical terms. Theoretically, the work aims to be synthetic and eclectic; it draws on all the main theoretical traditions in International Relations to explain the emergence of zones of stable peace – groupings of nations that succeed in escaping geopolitical rivalry. Empirically, the book ranges widely, covering twenty case studies that range from the thirteenth century through the present and span the globe.

I affiliate the book with the English School inasmuch as my analysis explores the intellectual terrain associated with the notion of international society – a defining concept for the English School. As I write in the book, “In a society of states, the social character of interstate relations overrides the rules of anarchic competition and power balancing” (17), laying a foundation for the emergence of pacifying bonds. My preference for the eclecticism and sociological bent of the English School is driven more by induction than deduction; the effort to explain stable peace led me in that intellectual direction. But this approach is also reflective of my view that realism, liberalism, and constructivism all fall short as explanatory theories when taken individually. It is my belief in the merits of theoretical eclecticism that has led me to self-identify as ‘a liberal realist with constructivist leanings.’

The reviewers generally see the theoretical and historical ambition of How Enemies Become Friends as an asset. Greg Anderson affirms that “the breadth and diversity of Kupchan’s approach genuinely appeals,” Stacie Goddard calls the book “breathtaking in its ambition,” and Seva Gunitsky writes that it is “unapologetically and pleasantly ambitious” and successfully “eschews the confines of paradigmatic divisions.” But they are also justified in viewing the book’s eclecticism as a liability. As Anderson continues, “the English School seemingly borrows from too many other traditions to become a systematized framework for looking at international relations.” And Goddard, while applauding the effort to bridge paradigms, questions whether my commitment to breadth might compromise the “depth and coherence” of my theory. She also questions the merits of shoe-horning disparate case studies into a common conceptual framework.

I accept that How Enemies Become Friends puts many different variables in play, and presents an argument about the causes of peace that might not be as parsimonious as one might like. But the book is problem-driven, not theory-driven. My primary aim is to explain when and how peace breaks out, and the eclecticism of the answer was needed to remain true to the facts. On the empirical front, I accept that, at least at first blush, it may seem an intellectual stretch to put into a common conceptual framework cases as wide-ranging as the Iroquois Confederacy, Sino-Soviet rapprochement, and ASEAN. But I stand by the book’s historical breadth. Indeed, as the book amply demonstrates, instances of stable peace exhibit striking similarity across time, space, and culture. It is that similarity that enabled me to discover a unified theory of the causes of peace – even if it is a theory that is at once rationalist and sociological in flavor.

Both Anderson and Goddard raise many pertinent questions that my book leaves unanswered. I acknowledge I could have gone to greater length to flesh out the political and coalitional circumstances that encourage leaders to risk policies of accommodation and practice strategic restraint toward their adversaries. I accept that my definition of the ‘strategic necessity’ that initially prompts the effort to turn enemies into friends comes in different forms; sometimes necessity is a function of external threat, while at other times it is a product of deteriorating political and economic conditions on the home front. And I share the reviewers’ frustration over the book’s incomplete explanation for when and why states move along the continuum of different kinds of stable peace – from rapprochement to security community to union. While my analysis does speak to many of the queries posed by the reviewers, I acknowledge that How Enemies Become Friends raises at least as many questions as it answers. However, I take that attribute to be not a shortcoming of the book, but a sign of the richness of the conceptual and empirical terrain that it explores.

Both Anderson and Goddard take me to task for not being more specific about the policy implications of my research. To be sure, those of us who seek to span the divide between scholarly inquiry and policy relevance could always say more about the implications of our research for decision makers. But How Enemies Become Friends makes more than a hefty contribution to policy making. The book demonstrates that diplomacy, not economic integration, is the currency of peace, and lays out a detailed diplomatic strategy for turning enemies into friends. It demonstrates that democracy is not a necessary condition for stable peace, and instructs democratic policy makers to take seriously the prospect of building productive partnerships with non-democracies. It also highlights the importance that policy makers should assign to social and cultural factors as they pursue peace. These, as well as other policy insights in the book, are hardly trivial contributions.

The review by Gunitsky is a bit of an outlier. He finds the analysis off target, claiming that my “beautiful theory” is “killed by ugly facts.” He bases this dismissal on three of the twenty historical cases in the book, arguing that I misinterpreted them. While How Enemies Become Friends runs over four hundred pages, his empirical critique runs four paragraphs. At least I earned from Gunitsky the compliment that “it is better to be wrong but interesting rather than right and trivially true.” For that accolade, and for the exertions of all the reviewers, I am thankful.

[1] Karl W. Deutsch, Political Community and the North Atlantic Area; International Organization in the Light of Historical Experience, (Princeton: Princeton University Press, 1957); Karl W. Deutsch, “Backgrounds for Community: Case Studies in Large-Scale Political Unification,” (unpublished manuscript: nd).

[2] Benjamin Cohen, “The Transatlantic Divide: Why Are British and American IPE So Different,” Review of International Political Economy 14, no. 2 (May 2007): 197-219.

[3] See Dale Copeland, “A Realist Critique of the English School,” Review of International Studies 29, no. 3 (July 2003): 427-441; Charles Glaser, “Structural Realism in a More Complex World,” Review of International Studies 29, no. 3 (July 2003): 403-414; Michael Desch, “It is Kind to Be Cruel: The Humanity of American Realism,” Review of International Studies 29, no. 3 (July 2003): 415-426.

[6] Perhaps most famously, see Stephen Krasner, “State Power and the Structure of International Trade,” World Politics 28, no. 3 (April 1976): 317-347.

[7] See e.g., M.G. Fry, “The North Atlantic Triangle and the Abrogation of the Anglo-Japanese Alliance,” The Journal of Modern History, vol. 39, no. 1 (March 1967): 46-64.

[8] See e.g., Otto Pflantze, Bismarck and the Development of Germany: The Period of Unification, 1815-1871, (Princeton: Princeton University Press, 1963).

[9] On democracies and economic integration and sources of stable peace, see Karl W. Deutsch, Political Community and the North Atlantic Area, Princeton: Princeton University Press, 1957; G. John Ikenberry, After Victory: Institutions, Strategic Restraint, and the Rebuilding of Order after Major Wars (Princeton: Princeton University Press, 2001).